Question

I am trying to implement a notifyicon (http://www.hardcodet.net/projects/wpf-notifyicon) in MVVM project. I understand this control is meant to be used in a regular WPF project.

I am wondering how to implement the ballon feature (Balloon feature).
As specified in this tutorial the method “ShowBallonTip” needs to be called

//show balloon with built-in icon
  MyNotifyIcon.ShowBalloonTip(title, text, BalloonIcon.Error);

The only place I could call this method, I can think of, is in the code behind. I do not have a problem with having a little code in a view code behind (even if I would prefer not having any) but I can not figure out how I can have the view model to talk to the view and asks it to call this method.

Even if I place this method in an event how can I raise this event programatically from the viewmodel?

Any idea how I could achieve this?

Answer 1

I have been able to display a balloon tip by initialising the icon in the viewmodel instead of the XAML.

Just calling the ShowBalloonTip method in my command do the trick.

I created a wrapper for the notify Icon:
NotifyService:

public class NotifyService : INotifyService
{
    private TaskbarIcon icon = new TaskbarIcon
        {
            Name = "NotifyIcon",
            Icon =
                new System.Drawing.Icon(
                    Application.GetResourceStream(Utils.FileUtils.MakeUri("/Icons/email.ico")).Stream),
        };


    public void Notify(string message)
    {

        icon.ShowBalloonTip("title", message, BalloonIcon.None);
    }

    public void ChangeIconSource(string path)
    {
        icon.Icon = new System.Drawing.Icon(
                    Application.GetResourceStream(Utils.FileUtils.MakeUri(path)).Stream);
    }
}

And I used it in my view model:
viewmodel

public class MainWindowViewModel : WindowViewModelBase
{
    private readonly INotifyService notifyService = new NotifyService();

    #region Fields
    private static HomeWindowViewModel homeViewModel = new HomeWindowViewModel();
    #endregion
    /// Initializes a new instance of the <see cref="MainWindowViewModel"/> class.
    /// </summary>
    public MainWindowViewModel()
        : base()
    {
        CurrentViewModel = homeViewModel;
    }

    #region Methods

    protected override void OnViewModelPropertyChanged(IViewModel viewModel, string propertyName)
    {
        int t = 2;
    }

    protected override void OnViewModelCommandExecuted(IViewModel viewModel, ICatelCommand command, object commandParameter)
    {
        int t = 2;
        notifyService.ChangeIconSource(@"/Icons/new_email.ico");
        notifyService.Notify("test");
    }
    #endregion
}